Private Lending secured by Mortgage

[Rob Henry]

Do you necessarily need a promissory note if you file a mortgage? Say for example, I lend someone $5,000 on a free & clear house (listed for sale with a Realtor) and file a mortgage for $10,000 once the house sells.

Would I need to fill out a promissory note as long as the mortgage is recorded with the county? Could I make it a performance mortgage with the "performance" being the sale of the house?

Also would this type of arrangement violate any usury laws? If there's no note I don't know if there would be any interest rate concerns.